lib/wlan/mlme/ap/tim.cpp

// Copyright 2017 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <wlan/mlme/ap/tim.h>

namespace wlan {

TrafficIndicationMap::TrafficIndicationMap() {
    aid_bitmap_.Reset(kMaxBssClients);
}

void TrafficIndicationMap::SetTrafficIndication(aid_t aid, bool has_bu) {
    ZX_DEBUG_ASSERT(aid < kMaxBssClients);
    if (aid >= kMaxBssClients) {
        errorf("attempt setting traffic indication for invalid aid: %zu\n", aid);
        return;
    }

    if (has_bu) {
        aid_bitmap_.SetOne(aid);
    } else {
        aid_bitmap_.ClearOne(aid);
    }
}

zx_status_t TrafficIndicationMap::WritePartialVirtualBitmap(uint8_t* buf, size_t buf_len,
                                                            size_t* bitmap_len,
                                                            uint8_t* bitmap_offset) const {
    size_t n1 = N1();
    size_t n2 = N2();

    *bitmap_len = 1 + (n2 - n1);
    if (buf_len < *bitmap_len) { return ZX_ERR_BUFFER_TOO_SMALL; }

    auto data = static_cast<const uint8_t*>(aid_bitmap_.StorageUnsafe()->GetData());
    memcpy(buf, data + n1, *bitmap_len);
    *bitmap_offset = n1 / 2;

    return ZX_OK;
}

size_t TrafficIndicationMap::BitmapLen() const {
    return 1 + (N2() - N1());
}

uint8_t TrafficIndicationMap::BitmapOffset() const {
    return static_cast<uint8_t>(N1() / 2);
}

const uint8_t* TrafficIndicationMap::BitmapData() const {
    return static_cast<const uint8_t*>(aid_bitmap_.StorageUnsafe()->GetData());
}

bool TrafficIndicationMap::HasDozingClients() const {
    bool empty = aid_bitmap_.Scan(1, aid_bitmap_.size(), false, nullptr);
    return !empty;
}

bool TrafficIndicationMap::HasGroupTraffic() const {
    return aid_bitmap_.GetOne(kGroupAdressedAid);
}

void TrafficIndicationMap::Clear() {
    aid_bitmap_.Reset(kMaxBssClients);
}

size_t TrafficIndicationMap::N1() const {
    size_t first_set_bit;
    bool none_set = aid_bitmap_.Scan(1, aid_bitmap_.size(), false, &first_set_bit);
    if (none_set) { return 0; }
    size_t n1 = first_set_bit / 8;
    return n1 % 2 == 0 ? n1 : (n1 - 1);
}

size_t TrafficIndicationMap::N2() const {
    size_t last_set_bit;
    bool none_set = aid_bitmap_.ReverseScan(1, aid_bitmap_.size(), false, &last_set_bit);
    if (none_set) { return 0; }
    return last_set_bit / 8;
}
}  // namespace wlan